On a sunny day in October 2002, I set up my homemade f/9 6-inch dobsonian solar reflector telescope on my back deck in San Rafael, California and observed the sun through a 25mm Kellner eyepiece. Each clear day for the next 60 days I sketched the whole solar disk, and noted the Macintosh sunspot classes of each active group, and counted the sunspots using the Wolf Sunspot counting method. When there were particularly interesting sunspots, I sketched the spots at higher magnification using a Televue 13mm Plossl or a 12mm Vixen Lanthanum. On some days I sketched the sun at H-alpha wavelengths using an f/6.8 70mm Televue Ranger refractor fitted with a Coronado SolarMax 60/T-Max 10 h-alpha filter and a 14mm Orion Lanthanum eyepiece. Why? To complete the Astronomical League's Sunspotter Club Solar observing program. Whole disk images are magnified 54x, sunspot images are 106x or 105x and h-alpha images are 34x. I used the Astronomical League's "Observe and Understand the Sun" booklet edited by Rik Hill as my guide for the project, and I'd like to thank him for the great booklet, and for tips, answers and many great solar resources.
ALPO - American Lunar and Planetary Organization collects data from amateur astronomers. Their drawing forms require a few pieces of information I had not thought to include in my Astronomical League sunspotter project, and as I gather the data on each sketch I'll add them to the individual pages. The first item is the Carrington Rotation Number. This is the number of rotations of the Sun's surface (as seen from the Earth) since November 9, 1853. The mean period for a single rotation of the Sun as seen from the Earth is 27.2753 days. My sunspotter program covered parts of three rotations: Rotation #1995 commenced on October 6, 2002. Rotation #1996 commenced on November 2, 2002. Rotation #1997 commenced on November 30, 2002.
|10/12/02 - full solar disk at 23:00 UT|
|10/12/02 - DKI and DKC active regions at 23:20 UT|
|10/12/02 - H-alpha view of solar disk at 23:30 UT|
|10/13/02 - full solar disk at 23:00 UT|
|10/13/02 - Three active regions - CSO, DAI and HRX at 23:30 UT|
|10/13/02 - H-alpha view of solar disk at 00:00 UT 10/14|
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